1. Field of the Invention
The present invention relates to a paper feeding device used in an office automation apparatus, such as an electronic copying machine, and an image forming apparatus provided with the paper feeding device, and more particularly, to a paper feeding device having a drawer-type paper cassette, which can be loaded into and unloaded from a cassette holding section, and an image forming apparatus provided with the paper feeding device.
2. Description of the Related Art
In general, paper feeding devices having a drawer-type paper cassette are designed so that paper sheets in the paper cassette are pushed up to a takeout position in a state ready for paper feed such that the cassette is securely held in a cassette holding section. In loading or unloading the paper cassette, a tray is released from a lifted state lest the paper sheets hinder the operation.
According to a conventional paper feeding device of this type disclosed in Published Unexamined Japanese Patent Application No. 2-233425, however, paper sheets in a paper cassette are kept up to be on standby without regard to the operation mode, and a tray is lowered when the cassette is to be loaded or unloaded.
Accordingly, if any subsequent paper sheets project from the paper cassette as a preceding paper sheet is taken out, that is, in case of "stay of paper at the delivery port," the projecting sheets sometimes fail to be restored to their regular position in the cassette even when the tray is lowered. This phenomenon frequently occurs when the residual quantity of the paper sheets in the cassette is small.
Thus, in the conventional paper feeding device, the paper sheets having once projected from the delivery port cannot be returned to their regular position in the paper cassette. As the cassette is drawn out, therefore, the projecting sheets are caught and damaged by the rear-side open edge portion of a cassette loading aperture. Removal of these damaged sheets is troublesome and uneconomical.